Reciprocating piston internal combustion engine with a cylinder housing and cylinder head consisting of a single block

ABSTRACT

A reciprocating piston internal combustion engine with a cylinder housing and cylinder head consisting of one block, in which the block extends over all cylinders of a cylinder row and the cylinder housing essentially consists of an inner wall and of an outer wall; the inner wall, together with a cylinder head delimits the cylinder space and the inner and outer walls are connected with each other by a cross wall arranged approximately at the height of the cylinder head bottom and extending over the entire block.

United States Patent Reisacher et a1.

1151 3,691,914 1451- Sept. 19,1972

1 1 RECIPROCATING PISTON INTERNAL COMBUSTION ENGINE WITH A CYLINDER HOUSING AND CYLINDER HEAD CONSISTING OF A SINGLE BLOCK Inventors: Josef Reisacher, Wendlingen; Al-

brecht Schmid, Stuttgart, both of Germany Assignee: Daimler-Benz Aktiengesellschaft, Stuttgart-Untertuerkheim, Germany Filed: July 21, 1970 Appl. No.: 56,783

I Foreign Application Priority Date July 26, 1969 Germany ..P 19 38 134.1

US. Cl. ..92/169, 123/193 CH, 123141.82 1111. C1 ..F01b 11/02 Field of searcnI'...,.llT;92/169; 123/4129, 41.28,

[56] References Cited UNITED STATES PATENTS 3,203,408 8/ 1965 Winkelman ..123/41 .82 2,700,964 2/1955 Nallinger ..123/193 CH 3,385,273 5/1963 Easter. ..123/41.82 3,351,044 11/1967 Pomeroy 123/41 .28 2,175,448 10/1939 Schlagintweit ..123/41.74

Primary Examiner-Martin P. Schwadron Assistant Examiner-R. H. Lazarus AttorneyCraig and Antonelli ABSTRACT 9 Claims, 2 Drawing Figures RECIPROCATING PISTON INTERNAL COMBUSTION ENGINE WITH A CYLINDER HOUSING AND CYLINDER HEAD CONSISTING OF A SINGLE BLOCK The present invention relates to a reciprocating piston internal combustion engine with a cylinder housing and cylinder head consisting of one single block, whereby the block extends over all cylinders of a cylinder row and whereby the cylinder housing essentially consists of an inner wall which, together with a cylinder head bottom, delimits the cylinder space, and of an outer wall separated from the inner wall by a cooling space.

With reciprocating piston internal combustion engines of the aforementioned type, there exists the danger that in the transition from the cylinder head bottom to the inner wall of the cylinder housing, incipient cracks result readily from the notch effect occurring thereat by reason of the force flow and thermal stresses. It has already been proposed heretofore to reduce the danger of cracks in that the inner wall is reinforced in proximity to the cylinder head bottom or in that individual braces or bars are provided between the inner and outer walls. However, as a result thereof, the inner wall is cooled non-uniformly within the area of the cylinder head bottom so that a reduction of the thermal stresses cannot occur.

The present invention is concerned with the task to so support and reinforce the transition between the cylinder head bottom and the inner wall that the danger of cracks within this area is eliminated or at least considerably reduced.

The underlying problems are solved according to the present invention in that the inner and the outer wall are connected with each other by a cross wall extending through the entire block and arranged approximately at the height of the cylinder head bottom.

The transition from the cylinder head bottom to the inner wall isfar-reachingly braced and relieved by the cross wall according to the present invention. The cooling of the inner wall takes place uniformly over the entire circumference thereof so that only slight thermal stresses occur. The present invention further entails the advantage that the cooling spaces in the cylinder housing and in the cylinder head are separated from one another so that two cooling medium flows result. It is thereby appropriate that the cooling medium flows at first through the cooling space between the inner and outer wall of the cylinder housing over the entire length of the block and thereafter-at the end thereof is conducted into the cooling spaces of the cylinder head.

Accordingly, it is an object of the present invention to provide a reciprocating piston internal combustion engine with a cylinder housing and cylinder head consisting of one block which eliminates by simple means the aforementioned shortcomings and drawbacks encountered in the prior art.

Another object of the present invention resides in intemal combustion engines with a cylinder housing and cylinder head made of one block, in which the danger of crack formation within the transition from cylinder head bottom to inner wall of the cylinder housing is farreachingly eliminated.

A further object of the present invention resides in a reciprocating piston internal combustion engine of the type described above, in which uniform cooling and minimization of thermal stresses is achieved by simple means.

These and further objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, one embodiment in accordance with the present invention, and wherein:

FIG. 1 is a partial longitudinal cross-sectional view through a multi-cylinder reciprocating piston internal combustion engine of in-line construction in accordance with the present invention; and

FIG. 2 is a partial horizontal section taken along line lI-II of FIG. 1.

Referring now to the drawing wherein like reference numerals are used throughout the two views to designate corresponding parts, the cylinder housing is generally designated by reference numeral 1 and the cylinder head by reference numeral 2 which are made in one single block that extends over all of the cylinders of the cylinder row. The separating surface with respect to the crank case (not shown) is designated by reference numeral 3. The cylinder housing 1 essentially consists of an inner wall 5 coordinated to each cylinder space 4 and of an outer wall 6 surrounding the inner wall 5 whereby a cooling space 7 is disposed between the inner wall 5 and the outer wall 6. An inlet channel 8 and an outlet channel 9, the mounting bore 10 of an ignition source (not shown), guide means 11 and 12 for inlet and exhaust valves (not shown) as well as a cooling space 13 are arranged in the cylinder head 2. The termination of the cylinder head 2 with respect to the cylinder space 4 is formed by a cylinder head bottom 14.

With reciprocating piston internal combustion engines of the aforementioned type, a notch place 15 exists in the transition between the cylinder head bottom 14 and the inner wall 5 conditioned on manufacturing reasons, from which incipient cracks can readily form. In order to avoid these cracks, the inner wall 5 and the outer wall 6 are connected with each other within the area of the transition between the cylinder head bottom 14 and the inner wall 5 by a cross wall 16. The cross wall 16 extends over the entire block so, that the cooling spaces 7 and 13 are completely separated from one another. A separate cooling medium conduction for the cylinder housing 1 and for the cylinder head results therefrom, for example, in such a manner that the cooling medium after flowing through the cooling space 7, is conducted at one end of the block into the cooling space 13.

While we have shown and described only one embodiment in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to those skilled in the art, and we therefore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

We claim:

1'. A reciprocating piston internal combustion engine comprising a cylinder housing and a cylinder head consisting of one block, the cylinder housing essentially consisting of an inner walland an outer wall, said inner wall and a cylinder head bottom delimiting at least one cylinder space, said outer wall being separated from the inner wall by a cooling space, said inner and said outer wall being connected with each other by a cross wall constructed one-piece with the cylinder housing and head structure and arranged approximately at the height of the cylinder head bottom, said cross wall extending over the entire block for separating the cooling spaces of the cylinder housing from the cooling spaces of the cylinder head, said cross wall being substantially thicker than each of the respective inner and outer walls whereby the cross wall provides reinforcing support to the upper ends of said inner and outer walls.

2. An internal combustion engine according to claim 1, characterized in that an internal groove is provided in said cross wall immediately adjacent the upper ends of the inner surface of said inner wall for providing clearance to machining tools used in machining the inner surface of said inner wall.

3. An internal combustion engine according to claim 2, characterized in that said internal groove is an annular groove extending around the inside of the top of the cylinder space.

4. An internal combustion engine according to claim 3, characterized in that an inlet and an outlet guide aperture is provided in said cylinder head for each cylinder space, and in that a connecting wall between said inlet 'and outlet guide apertures extends downwardly to approximately the plane of the upper extent of said annular groove.

5. An internal combustion engine according to claim 2, characterized in that the cooling spaces of the cylinder head and of the cylinder housing are connected with each other only at one end of the cylinder housing.

6. An internal combustion engine according to claim 2, characterized in that the connection between the cooling spaces is made in such a manner that the cooling medium first flows through the cooling spaces of the cylinder housing and thereafter is conducted into the cooling spaces of the cylinder head.

7. An internal combustion engine according to claim 1, characterized in that the engine includes a plurality of cylinders and in that the block extends over all cylinders of a cylinder row.

8. An internal combustion engine according to claim 5, characterized in that the cooling spaces of the cylinder head and of the cylinder housing are connected with each other only at one end of the cylinder housing.

9. An internal combustion engine according to claim 5, characterized in that the connection between the cooling spaces is made in such a manner that the cooling medium first flows through the cooling spaces of the cylinder housing and thereafter is conducted into the cooling spaces of the cylinder head.

* 1.! IR l l 

1. A reciprocating piston internal combustion engine comprising a cylinder housing and a cylinder head consisting of one block, the cylinder housing essentially consisting of an inner wall and an outer wall, said inner wall and a cylinder head bottom delimiting at least one cylinder space, said outer wall being separated from the inner wall by a cooling space, said inner and said outer wall being connected with each other by a cross wall constructed one-piece with the cylinder housing and head structure and arrangeD approximately at the height of the cylinder head bottom, said cross wall extending over the entire block for separating the cooling spaces of the cylinder housing from the cooling spaces of the cylinder head, said cross wall being substantially thicker than each of the respective inner and outer walls whereby the cross wall provides reinforcing support to the upper ends of said inner and outer walls.
 2. An internal combustion engine according to claim 1, characterized in that an internal groove is provided in said cross wall immediately adjacent the upper ends of the inner surface of said inner wall for providing clearance to machining tools used in machining the inner surface of said inner wall.
 3. An internal combustion engine according to claim 2, characterized in that said internal groove is an annular groove extending around the inside of the top of the cylinder space.
 4. An internal combustion engine according to claim 3, characterized in that an inlet and an outlet guide aperture is provided in said cylinder head for each cylinder space, and in that a connecting wall between said inlet and outlet guide apertures extends downwardly to approximately the plane of the upper extent of said annular groove.
 5. An internal combustion engine according to claim 2, characterized in that the cooling spaces of the cylinder head and of the cylinder housing are connected with each other only at one end of the cylinder housing.
 6. An internal combustion engine according to claim 2, characterized in that the connection between the cooling spaces is made in such a manner that the cooling medium first flows through the cooling spaces of the cylinder housing and thereafter is conducted into the cooling spaces of the cylinder head.
 7. An internal combustion engine according to claim 1, characterized in that the engine includes a plurality of cylinders and in that the block extends over all cylinders of a cylinder row.
 8. An internal combustion engine according to claim 5, characterized in that the cooling spaces of the cylinder head and of the cylinder housing are connected with each other only at one end of the cylinder housing.
 9. An internal combustion engine according to claim 5, characterized in that the connection between the cooling spaces is made in such a manner that the cooling medium first flows through the cooling spaces of the cylinder housing and thereafter is conducted into the cooling spaces of the cylinder head. 